Electromagnetic wave reflectors are used in the design of antennas in the telecommunication field. The antennas are in particular used in space applications to equip telecommunications satellites. An antenna with a conventional configuration is composed of a radio frequency source and a reflector with a parabolic form whose concave reflector surface constitutes the active surface. A source is placed at the focal point of the reflector and is designed to emit or receive electromagnetic radiation focalized by the reflector. The reflector can also have other shapes than parabolic, e.g. convex or numerically determined.
Certain applications require large reflectors. However, in any type of space application there is always a need for weight optimization. It is therefore essential to find a reflector which may be made light-weight without losing the required electromagnetic properties.
U.S. Pat. No. 6,018,328 discloses a light-weight reflector having a reflector shell made of a polymeric laminate material and the shell is supported of a backing structure on the back surface of the shell. The backing structure is formed on silicon mandrels loosely on the reflector shell and is made of polymeric laminate material. After curing the backing structure, the mandrel is removed and the structure is arranged on the reflector shell by means of integral clips.
In EP 948 085 is a reflector shown having a backing structure. The reflector dish is formed of a graphite composite laminate and the backing structure is formed of upstanding integral ribs cut from flat laminate.
U.S. Pat. No. 2,747,180 discloses a reflector with a honeycomb core. The reflector construction gives a light weight and rigid reflector that does not require a separate support structure. The reflector is a sandwich construction which may be manufactured by performing multiple operations in a mould tool.
The inventor has developed a light-weight reflector and a method of manufacturing a reflector which is disclosed in EP 1 589 612. A first skin is arranged on a mould, where after a core is arranged on the skin, and then the assembly is cured. The core is then machined to a pattern which forms the backing structure. A second skin is arranged on the core and the complete assembly is cured. The reflector is light-weight and has good thermal properties.
In space applications, the antennas need to be as light as possible so as to facilitate the placing in orbit of a satellite equipped with antennas with reflector dishes. The reflectors also need to be stiff. There is a need to produce light-weight reflectors having good properties, wherein the production method is easy to apply, not so time-consuming and not so expensive.